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<title>Ready Help: Hints and Tips</title>
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<p>
<h3>Some useful hints and tips</h3>

<p>
<ul>
<li>To view a pattern file just drop it onto the Ready app, or onto the
rendering window if the app is already running.
<li>Rendering complex scenes can be quite costly, so to increase the speed you can turn off the
displacement mapped surfaces, and turn off the display of multiple chemicals. See the Render
Settings in the Info Pane.
<li>For maximum speed, use <a href="action.html#Action_ChangeRunningSpeed">Change Running Speed...</a>
in the Action menu to increase the number of timesteps between each render. Fewer frames will be
drawn, and the overall speed will be faster.
<li>The patterns in the "CPU-only" folder typically run much slower than the others, if your
graphics card is reasonable. So for better performance you shouldn't use them. (If you don't have
OpenCL installed or you're in a virtual machine then only the CPU-only patterns will work.)
<li>Any image-based reaction-diffusion pattern (vti files, not yet the vtu mesh ones) can be changed in
size using the dimensions control in the Info Pane. If you want the size of the stripes and spots to grow
then usually some of the parameters must be altered. Some examples:
    <ul>
    <li>With
    <a href="open:Patterns/GrayScott1984/Pearson1993.vti">GrayScott1984/Pearson1993.vti</a> there is an explicit
    parameter for scale, <tt>dx</tt>, which is used in the computation of <tt>laplacian_a</tt> and <tt>laplacian_b</tt>. If you double the size of the
    pattern (to 512x512x1), you can set <tt>dx</tt> to half (0.004883) to get the same size of stripes as the
    original. For numerical stability at the new size, change timestep to 0.3.
    <li>There is no <tt>dx</tt> parameter in <a href="open:Patterns/GrayScott1984/U-Skate/Munafo_glider.vti">GrayScott1984/U-Skate/Munafo_glider.vti</a> but you can add one using <a href="action.html#Action_AddParameter">Add Parameter...</a> on the Action menu. Set it to 0.8 to make the glider bigger. Going larger still will need you to increase the pattern dimensions and to reduce the timestep. This combination works: 256x128, dx=0.5, timestep=0.5.
    <li>The initial pattern generator (that draws the rectangles in that example) works relative to the size of the image, so changing the ratio of height to width affects how it works. Notice that you need to keep the dimensions in approximately the same ratio for the glider to work.
    </ul>
<li>To make a video, use the command on the File menu: <a href="file.html#File_StartRecording">Start
Recording...</a> to produce a sequence of images. Then use your favorite utility to make a video
file. For example in <a href="http://ffmpeg.org/">FFmpeg</a> the following command makes a high
quality <a href="http://en.wikipedia.org/wiki/MPEG-4">MPEG-4</a> video at 50 frames per second:
<br><tt>ffmpeg -r 50 -i frame_%06d.png -vb 5M -vcodec libx264 video.mp4</tt>
<li>To make an animation of meshes, use the command on the File menu: <a href="file.html#File_StartRecording">Start
Recording...</a> and select '3D surface' as the image source. With the filename extension set to .obj or .ply,
you can then use the <a href="https://github.com/neverhood311/Stop-motion-OBJ">Stop-motion-OBJ</a> add-on in Blender to
import the files. (And if you want to use the vertex colors then choose the .ply format.)
<li>If your 3D mesh resolution is too low, use an external tool like
<a href="http://meshlab.sourceforge.net">MeshLab</a> to subdivide it before importing into Ready.
<li><a href="http://www.paraview.org">ParaView</a> can load the output of Ready (vtu and vti files)
and has lots of filters to try. A method for making wrinkly rabbits was discussed
<a href="http://www.conwaylife.com/forums/viewtopic.php?f=7&t=945">here</a>.
</ul>

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